im soo stresseddd, gcse historyy help

I'm doing ocr history and am in Year 11 but I reckon the principles are similar, so I really recommend practicing exam-style questions as much as possible because the way you answer the question is as important, if not more important than your knowledge. My history teacher hadn't done this very much and had a basic overview of answering each question which they told us which I really hate, because questions such as source questions are often really weirdly worded, and having a set answer structure is sO much more helpful.
Secondly you'll probably be overwhelmed with dates BUT don't panic! If you can't remember an exact date (unless it's a very important one such as the 1875 public health act), it's ok to basically paraphrase them like 'in the late 1750's' for example, and as far as I'm aware it's also unlikely you get marks taken off for one wrong date.
I haven't used a revision guide at all for my revision (but I'm still working at a grade 8/9 level) instead I basically took the textbook and created huge timelines for each topic (this really helps to get rid of any ordering issues because the stupid textbooks often don't do things in chronological order) and also do a lot of past paper questions in my own time. Seneca is really good as well (but for me they did not have all the OCR topics) for knowledge learning too. I also advise trying to make things seem as interesting and somewhat stupid which can help remembering them- for example to remember who had major impact on public health during the industrial era we have the saying 'acts, facts, taps and crps' to refer to Chadwick, Pasteur, Snow and Bazelgette, and it's much easier to remember.
I hope this helps!